The use of clays to sequestrate organic pollutants. Leaching experiments.
Leaching experiments are performed from clay-pollutant systems in order to evaluate the capability of clays to sequestrate organic pollutants from wastewaters. Reference kaolinite KGa-1b, montmorrillonite SWy-2 and reference soil BCR-700 are the sorbent materials. 2,4,6-trichloroaniline (2,4,6-TCA) and 4-chlorophenol (4-CP) are the typical pollutants, sorbed at amounts of 10.0 mg g(-1) and 5.8 mg g(-1) on SWy-2 and 7.3 mg g(-1) and 2.2 mg g(-1) on KGa-1b, respectively. The leaching agents are ultrapure water and model solutions of acid rain and surface waters that simulate meteoric leaching. 1.0mM HNO(3), 1.0mM H(2)SO(4) solutions and a methanol/water 50/50 (v/v) mixture simulate leaching agents of industrial source. The results are compared and the preferential capability of the clays to sequestrate the more lipophilic 2,4,6-TCA is evidenced. The bond interactions are discussed and explained through preferential adsorption reactions. For montmorrillonite also a simultaneous intercalation in the phyllosilicate interlayer is proposed.
Gianotti
V
V
DISAV-Dipartimento di Scienze dell'Ambiente e della Vita, University of Piemonte Orientale, Alessandria, Italy.
Benzi
M
M
Croce
G
G
Frascarolo
P
P
Gosetti
F
F
Mazzucco
E
E
Bottaro
M
M
Gennaro
M C
MC
D015258:Acid Rain; D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry*; D000814:Aniline Compounds / Q000737:chemistry / Q000302:isolation & purification; D001546:Bentonite / Q000737:chemistry; D002733:Chlorophenols / Q000737:chemistry / Q000302:isolation & purification; D000077215:Clay; D004785:Environmental Pollutants / Q000737:chemistry* / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007616:Kaolin / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry* / Q000302:isolation & purification*; D012015:Reference Standards; D012987:Soil; D014867:Water / Q000737:chemistry
D015258:Acid Rain; D000538:Aluminum Silicates; D000814:Aniline Compounds; D002733:Chlorophenols; D004785:Environmental Pollutants; D007220:Industrial Waste; D009930:Organic Chemicals; D012987:Soil; D014867:Water; D001546:Bentonite; D007616:Kaolin; C029107:4-chlorophenol; C045381:2,4,6-trichloroaniline; D000077215:Clay